Compounded mineral oil



Wutentecl Feb. it, laid No llllravving. Application Zl'anuary l3, i941; Serial No. $714,242

(ill. 252-35) l2 @laims.

s invention relates to a new and useful cpositlon of matter and involves a composition comprising a viscous hydrocarbon oil and a polyvalent metal salt of certain substituted acids of phosphorus.

This application is a continuation-in-part of our parent application Serial No. 241,648, filed November 21, 1938, issued as Patent No. 2,228,659 on January 14, 1941, and is directed to a divisionial aspect of the invention disclosed in the parent case.

The production of improved hydrocarbon oils and particularly of lubricating oils having desired characteristics has been the subject of extensive research and investigation in recent years. Generally speaking, the compounding of hydrocarbon oils to obtain desired characteristics involves empirical phenomena and the action of untested types or compounding agents cannot be predicted.

A characteristic which has been the subject of extensive investigation is the tendency of hydrocarbon oils to deteriorate or partially decompose and oxidize when subjected to high temperatures. This deterioration is evidenced by the deposition of adhesive deposits on hot metal surfaces over which the hydrocarbon oil may flow. It is important that resistance to such deterioration be imparted to hydrocarbon oils, particularly to lubricating oils, in order that such compositions may be relatively free from the tendency to form such deposits even under high temperatures and severe operating conditions. A direct result of this type of deterioration during lubrication of internal combustion engines, such as engines of the Diesel type, is the tendency of the oil to cause or permit the sticking of piston rings.

The crankcase lubricant in internal combustion engines is subjected to extremely severe operating conditions and in engines of the Diesel type the lubricant encounters in the piston ring zone temperatures of from approximately 425 to 650 F. and pressures from the oxidizing combustion cases as high as 750 to 1150 lbs. per sq. in. Addition agents which render hydrocarbon 0115 resistant to deterioration by heat at high temperature levels in the orderof those above mentioned usually impart to'the oil the ability to inhibit piston ring sticking in internal combustion enclues and not longer periods of operation of such engineswithout the necessity of major overhauls heretoforecccasioned by stuck piston rings.

It shouldbe noted that stabilizing agents which are edectiveat lowtemperatures to impart increased stability to hydrocarbon oils, or which are nature, are highly empirical and require extene to such stabilizers therefore cannot serve as a guide for one seeking stabilizing agents or oxidation inhibitors efiective at higher temperature levels. The phenomena involved are catalytic in sive experimentation to determine the action of a given type of addition agent.

The present invention involves the discovery that dispersion of polyvalent metal salts of substituted oxyacids of phosphorus in hydrocarbon oils such as mineral lubricating oil imparts new,

' unpredictable and highly desirable properties to cations as, for instance,

the composition. These new properties render the compounded oil particularly useful for various purposes. Although increased resistance to deterioration .at high temperature levels comprises one of the principal advantages of the compounded oils of this invention, it is to be understood that the invention is not limited to this feature, that different compounds of the general type herein involved vary in their degreeor effectiveness and may impart one or more other desirable properties to the lubricating composition. For example, certain of the compounds reduce'the amount of wear produced as compared with a straight uncompounded mineral oil. The same or other compounds inhibit the corrosion of copper-lead or cadmium-silver bearing metals, etc. In general, however, it has been discovered that the new compositions herein disclosed are more stable to heat than is a hydrocarbon oil with which thdcompositions are compounded. The new compositions of this invention are therefore useful where resistance to deterioration by heat is important. An example of such utility, other than as a lubricating 011, comprises use as a heat transfer fluid where it may be desirable to inhibit or prevent the formation ofa deposit on the metal surfaces fromor to which heat is being conveyed. Likewise, the increased resistance to oxidation imparted to the oil by the compounds of this invention will find various-applior transformer oil.

,an insulating, switch,

It has also been discovered t certain metal salts of substituted omhosphoric acids have a combination of properties heretofore unknown and particularly desirable in compounded mineral oil, namely, the ability to inhibit omdation and impart to lubricating oils increased resistance to deterioration by heat, the ability to inhibit piston ring sticking, freedom from the production of increased wear on cylinder walls and piston rings as compared with uncompounded mineral oils, and low corrosivity as respects the chemical action of the compounded oil on hear ing metals such as cadmium-silver and copperlead alloys. Although various compounded mineral oils are known which are capable of inhibiting piston ring sticking, the discovery of specific compounding agents capable of imparting the above combination of properties to hydrocarbon oils represents an unobvious and important contribution. 7

Metal salts of substituted oxyacids of phosphorus which may be added to hydrocarbon lubricating oils to provide a new composition of matter of the type herein involved comprise the salts of metals selected from groups 11, III, IV and VI of Mendeleeif's Periodic Table of the Elements. Specific examples of such metals are aluminum, calcium, barium, strontium, chromium and magnesium. Salts of iron, cobalt, nickel, zinc, tin

and lead comprise additional examples of compounds falling within the broader aspects of the invention.

The metal salts of this invention are preferably formed from substitued oryacids of pentavalent phosphorus of the following type formulae:

OR R

. =P\ or 0=Pt) B l on on where R and R may be alkyl, aryi, alkaryl, aralkyl or cyclic non-benzenoid' radicals. Suhstituted phosphoric acids containing at least twelve carbon atoms are preferred. mamples oi preferred type acids are allryl or alkaryl substituted phosphoric acids having at least twelve carbon atoms in the molecule. However, it is to be understood that the broader aspects of the n-P ph bouic we;

3 on up \P-0I{ phosphinic acid.

In all of the above formulae R and R may be mouoester of phospbonic add;

alwl, aryl, alkaryl, aralkyl or cyclic non-b noid groups.

In general, polyvalent metal salts of substituted-derivatives or oxyacids of phosphorus such as phosphorous acid, hypophosphoric acid, HzPOn; orthophosphoric acid, H904; pymphoophoric acid, HQPSOI; ran within the broadest plate.

' invention include the use 01' other types of sublid aspects oi the invention. By "substituted" or "substituted derivatives 0 acids of phosphorus whenever used herein, it is intended to designate acids containing an organic group oi. the type previously listed, 1. e., alkyl, aryl, alkaryl, aralkyl, or cyclic non-benzenoid groups. The organic groups may be either directly attached to the phosphorus atom of the compound or attached thereto through an intervening atom such as oxygen. The term onyacids of phosphorus" is intended to designate throughout the specification and claims acids of phosphorus in which one oxygen atom may intervene between the hydrogen and phosphorus atoms of the ester.

The preferred acids are substituted orthophosphoric acids and th preferred salts comprise the aluminum, calcium, barium and chromium salts of these acids. Examples of such salts are aluminum lauryl phosphate, aluminum cetyl phosphate, aluminum octadecyl phosphate, aluminum spermol" phosphate, aluminum oleyl phosphate, aluminum spermenyl phosphate, aluminum cetyl phenyl phosphate, aluminum dii'amylphenyl) phosphate, aluminum naphthenyl phosphate, calcium lauryl ph0sphate, calcium cetyl phosphate, calcium octadecyl phosphate. calcium spermol phosphate, calcium oleyl phosphate, calcium "spermenyl phosphate, calcium cetyl phenyl phosphate, calcium di- (amylphenyl) phosphate, calcium naphthenyl phosphate, chromium lauryl phosphate, chromium cetyl phosphate, chromium octadecyl phosphate, chromium spermol" phosphate, chromium oleyl phosphate, chromium spermenyl phosphate, chromium cetyl phenyl phosphate, chromium di- (amylphenyll phosphate, chromium naphthenyl phosphate, barium lauryl phosphate, barium cetyl phosphate, barium octadecyl phosphate. barium spermor phosphate. barium oleyl phosphate, barium "spermeny phosphate, barium cetyl phenyl phosphate, barium di-(amylphenyl) phosphate, and barium naphthenyl phosphate.

Additional examples of salts within the scope of the invention are: aluminum di-cyclohexanyl phosphate, aluminum di-stearo-glyceryl phosphate, aluminum tetra-chloro-octadecyl phosphate, aluminum di-(G-chloro, 2-pheuyl phenyl) phosphate, aluminum di-(3-methyl, 4-chloro phenyl) phosphate, calcium di-cyclohexanyl phosphatacalciumdi-stearo-glycerylphosphatacalcium tetra-chIoro-octadecyl phosphate, calcium diiii) (il-chioro, 2-phenyl phenyl) phosphate, calcium di-(Zi-methyl, 4-chloro phenyl) phosphate, chromium di-cyclohexanyl phosphate, chromium di- -glycerylphosphate,chromiumtetra-chloro it a i chromium di-(B-chloro, 2- w phenyl) phosphate, chromium di-(3- l, 4-chloro nhcnyl P p magnesium M t i w i Ir: 11m, magnesium phosphate, um tetrachlamtva be, magnesium (ll-(6 chloro, a-phcnyl phenyl) phosphate, m di-(Ii-l, 4-chloro Dhen'yD phosphate, magnw m lauryl phosphate, magnesium cetyl phos- Mr o w: yruullil mam], magspermol phosphate, um oleyl abate. mum "snermenrl" p osp a cetyl phsnyl phosphate, di-(amylphenyl) phosphate. magnesium naphthenyl phosphate, barium di-cyclohexanyl phosphate, barium di-stearo-glyoeryl phosphate, barium tetra-chloro-octadecyl phosphate, barium di-(fi-chloro, Z-phenyl phenyl) phosphate. and barium di-(3-methyl, Q-chloro phenyl) phossmarts where it is an alkyl radical. The alkyl ethyl phosphoric acid is soluble in ether, while the ethyl metaphosphate is not and the ether solution of the former may be separated from .the latter by decantation. Table 1 gives a number of examples of substituted phosphoric acids suitable for the purposes of this invention and a brief indication as to their method of preparation.

TABLE 1 Acid Method of preparation Mogo-cetylphos- 9.25 lb. cetyl alcohol and 5.01 lb. 1 .0. were p one.

Mono-"spermoP refluxed with 5523i. ethyl ether for 24 hrs. Cetylphosphoric aci solution decanted. 112 gins. solid sperm alcohols, 60 gms. P205. and

phosphoric. 400 gms. ethyl ether treated as above. Mono-octadecyl- 100 gins. octadecanol and 150 cc. benzene treated phosphoric. with 56.8 gins. P0013. Product was hydrolyzed to give a free acidic hydrogen. Di-(6-ehloro-2- 100 gins. oi the phenol and 50 gins. P105 heated phenyl-phenyl) to 180 for 18 hrs. phosphoric. I Mono-oleylphos- 107 gms. oleyl alcohol and 28.5 gms. P10 were phoric. refluxed in ethyl ether for 24 hours. Mono-sperm- 107 gins. liquid sperm alcohols and 27 gins. P105 egyl phosrefluxed in ethyl ether for 24 hrs. p one. i. Dicyelohexanyl 150 gins. cyclohexanol and 87 gms. P205 refluxed Cphosphoric. with 150 gms. ethyl ether [or 24 hours. etylphenyl) 688 gins. cetyl phenol and 316 gins. P205 refluxed phosphoric. with ethyl ether for 24 hrs. D1-(amylphenol) 100 gins. amyl phenol and 43 gins. P205 heated to 185 F. for 15 hrs. 190 gms. totraehloro-octadocanol and 28 gms.

P305 refluxed with ethyl ether for 17 hrs.

phosphoric.

M o n o t e t r a chlorn) octadecylphosphoric.

in preparing the metal salts herein involved,

the ethyl group in the ethyl phosphoric acid above mentioned may be hydrolyzed oil to form the metal salt of the mono-alkyl-ortho-phosphoric acid, i. e. the salt of RHzPOr. The type of operation is not limited to the alkyl derivatives but includes aryl-ethyl-phosphoric acid, alkarylethyl-phosphoric acid, aralkyl-ethyl-phosphoric acid and ethyl phosphoric acids containing a cyclic non-benzenoid group.

The aluminum salts may also be prepared in an environment substantially free of water by the reaction of aluminum chloride with the free substituted acids of phosphorus. However, such aluminum salts have properties different from the salts prepared by precipitation from aqueous solutions. The salts prepared in a non-aqueous environment are soft, low-melting solids, while the corresponding salts prepared by precipitation from aqueous solutions are hard, non-melting solids. Although the former type of salt may be utilized for imparting some desirable properties to hydrocarbon oils, it is preferred to use a salt prepared by precipitation from aqueous solutions where the ability to inhibit piston ring sticking inlubricating oils is desired.

The cobalt, nickel, zinc, tin'and lead salts mentioned at page 4, line 19; and the oils containing the same may, by way of exempliflcation, be prepared as follows:

Cobalt cetyl phosphate: 100 gms. of cetyl phosphoric acid were suspended in 2 gallons of Water. This was neutralized with a 10% solution of potassium hydroxide, heated to 190 F.

The metal salts of the various substituted oxyacids of phosphorus may be conveniently prepared by reacting the acid with sodium hydroxide or potassium hydroxide and then precipitating the desired metal salt from the solution of the sodium or potassium salt by the addition of the appropriate metal ion. The salt may also be prepared by the direct neutralization of the acid as, for example, with lime Where the calcium salt is to be obtained.

- Basic aluminum salts prepared by the precipitation method are preferred by reason of their low corrosivity to alloy bearing metals. although the so-called normal salts are not precluded. It is also preferred to maintain the amount of .co-precipitated alkali metal salt in the heavy metal compoundsat a minimum because the alkali metal salts decrease the stability of the oil solution in the presence of water.

The calcium salts may also be prepared in the non-aqueous environment by the reaction of calcium carbide with the free substituted acidsof phosphorus.

and the cobalt salt precipitated by adding an exce ss of a 10% cobalt chloride solution. 354 gms. or air acid refined naphthenic base S. A. E. 30 mineral lubricating oil were stirred in until it had picked up and dissolved the precipitated cobalt salt. The oil concentrate of the salt so produced was removed from the water by decanting and then washed several times by working with fresh water. The concentrate was dried by heating. The finished concentrate contained 25% by Weight of cobalt cetyl phosphate. This concentrate was then added to an appropriate lubricating oil in the amount required to yield the proportions desired and hereinafter described.

Nickel cetyl phosphate was prepared by the method above described and using nickel chloride solution (NiCla) for precipitating the nickel cetyl phosphate from the potassium cetyl phosphate solution.

Zinc cetyl phosphate was prepared by the method above described and using zinc chloride solution (ZnClz) for precipitating the zinc cetyl phosphate from the potassium cetyl phosphate solution.

Tin cetyl'phosphate was prepared by the meth- 0d above described and using stamens chloride solution (511012) for precipitating the tin cetyl phosphate from the potassium cetyl phosphate solution.

Lead cetyl phosphate was prepared by the method above described and using the following proportions of ingredients:

Cetyl phosphoric acid grns Water -i; gal1ons 2 KOH solution pcr cent; 10 Lead acetate solution do 10 Lubricating oil gms 164 I By way of illustration and to demonstrate the unique-= properties possessed by the compounded oils of this invention, data from extensive tests are given in Table 2.

Team 2 Miscellomemts tests Engine tests, Lauson Strip corrosion Preparation of compound Weeks C d t i Viscos 11 1 ompoun can Rm c as salt fitick Cleanliness Cu-Ph (Dd-Ag 3 2?, Acid prepmd ing o from- Acid treated western 011 o 1. 0 Poor 1. 0 1. 0 477 1. 0 Aluminum lauryl phosphate"- 1. 0 5. 0 Good 0. 1 l. 5 546 Colngiercial lauryl phosphoric Na salt ac D0 0.05 1 0 195 -.d0 D0. Aluminum cetyl phosphate. 1.0 6. Cetyl alcoho1+P1Ot+ether... Do. Do"; 0.1 4. .d0 Do, Do 0.8 5 -.d0 Ksalt. Aluminumoctadeoylphosphate. 0.15 5. 1. Octadecyl alchohl+POCh+ Na salt.

s u t. Aluminum spermol" phos- 1.0 5.0 O Selig sperm aicohols+P O Do.

ha 0 er. p D? 0.1 5.0 1.0 1.0 do Do, Aluminum oleyl phosphate. .1 0. 7 4. 0 0. 1 1. 0 Oleyl alcchol+P1Os-i-ether.- Do. Aluminum spermenyl phos- 0. 3 2.0 0.1 0.2 Lug-filed sperm a1cohol+P:Ot+ Do. hate. e r.

Afiihminlrlim di-cyclohexanyl 0.1 5.0 Very E 0 Cyc1ohexan01+P10s+cthcr. Do.

osp ate. Afulniimlilmm di-(amyl-phenyl) 1.0 .0 F811 0. -0 Amy1phenol+Pz05.

us a 1 A umlgum d -stearo-slvoery 0-7 Glyceryl d1stearate+P O Phosphate. 1 ether. A uminurn tetra-chloro'octa- 0.1. .-...do 0.2 3.0 201 Tetra-eh1oro-octadecano1+ Do.

decyl phosphate. t+ether. Calcium lauryl phosphate L0 2.0 do 1.0 5.0 451 Commercial lauryl phosphoric Do.

ac Excellent...v 156 Cetyl aiooho1-I-P;0t+ether. Ksalt.

220 do 0 199 d0 Do. Magnesium lauryl phosphate- 401 Commercial lauryl phosphoric Do.

. ac Aluminum laurylphosphite... 284 Laurylalcohol+PCh Do.

1 Expressed as ratio of time to stick rings of compounded oil to that with an unco Expressed as ratio of compounded oil corrosion to corrosion with Western ncid re Expressed as ratio of wear ofvcompounded oil to that of Western acid refined 011 S. A. E. 30

mflpounded Western acid refined oil S. A. E. 30.

ned oil 8. A. E. 30.

The base oil used [or testing the addition agent was in all cases an acid refined Western oil S. A. E. 30 grade.

Theabove data show that small amounts of most of the addition agents act as corrosion incylinder 2% inch bore, 2% inch stroke Lauson gasoline engine was operated under extremely severe conditions for the purpose of developing iully piston'ring sticking and piston gumming tendencies under circumstances simulating severe operating conditions encountered in the field. Operation of the motor during tests was continuous at 1600 R. P. M. except for shut-downs at fifteen-hour intervals for inspection. .The jacket temperature was maintained at 375F. and the sump oil temperature at 220 F.

7 The wear tests were carried out in a Weeks machine comprising a 5 inch steel ball pressed against a 1% anch'steel cylinder with a pressure of a0 lbs., the cylinder dipping in the oil to be tested and rotating at 600 R. P. M. The duratlon of the test was sixteen hours and the wear rate determined by measuring the amount of metal removed from the ball. In the above wear tests the lubricant was maintained at approximately 300 F. as indicated;

The corrosion tests were carried out in the following manner: Glass tubes '2 inches in diameter and 20 inches long were immersed in an oil bath, the temperature of which was automaticallfi controlled to within :1" F. of the test temperature which was-300 F. Approximately 300 cc. of oil under the test was placed in each tube and air was bubbled through it at the rate of 10 liters per hour. Strips of the difierent types of beer-- ing metals were cut to size and placed in the oils; in most cases the copper-lead mixture and cadmium-silver bearing alloys were tested simultaneously in the same sample of oil. The weight loss of each strip was recorded. Before weighing, each strip was washed in petroleum ether and carefully wiped with a soft cotton cloth. The duration of the test was 72 hours.

. To further illustrate the corrosion inhibiting properties of the compounding agents herein disclosed. the following data obtained in the above type strip corrosion test are given:

TABLE 3 an rea 3521 egg Penns l- Bearing metal/oil g m m *3 1;

co phosphate Weight loss miliigrams-wpper-lead 76. 4 7. 3 Weight loss milligrams-eadmium-silver 61. 3 0. 0 Weight loss milligrams-lead 415. 4 267. 4 Use oil inspections:

Increase in viscosity at F 458 133 Increase in viscosity at 210 F 18. 7 3. 8

Neutralization No. .i 0. 65 0. 67

In an identical strip corrosion test after 72 hours at 300 F. 1% cobalt cetyl phosphate decreased the loss in weight on a copper-lead hearme by 11.9 mm., lowered the viscosity increase Ditto-i-l% lead cetyl phosphate asi ivr 23% seconds Saybolt at l hi, and lowered the naphtha insolubles (A. S. T. M.) formed by too.

The limiting adhesion temperature is a sigcant property of lubricating oils, an increase in the limiting adhesion temperature being desirable. In a test designed to measure this property, a trough is tilted at a 1 angle and heated at its lower end only so that a temperature gradient from the hotter lower end to the measure of the ability of the oil to lubricate and spread over but surfaces such as the upper portions of the cylinder walls of internal combustion engines. Obviously, the higher the limiting adhesion temperature the greater the efficiency of the lubricant under the adverse conditions typifled. The following data show the improvements produced, by way of example, with cobalt and lead salts:

TABLE l Limiting adhesion temperature F.

Oil

Acid refined naphthe'nic base S. A. E. 30 Ditto+l% cobalt cetyl phosphate.

in order to measure the ability of stabilizing agents to prevent or inhibit deterioration of the oil. color sta ility tests were carried out as follows: Weighed amounts of the oils under test were placed in to ml. beakers and set on a heated copper block having a uniform temperature distribution. The beahers were of uniform crosssection so that the level of the oil was the same distance from the bottom of the beaker in each Taste 5 Color stability Color Paratfinlc base S. A. E.

Ditto-i-.5% nickel cetyl phosphate Ditto+.5% zinc cetyl phosphate D tto+.5% tin cetyl phosphate. l)ltto+.5% manganese cetyl phosphate Acid refined naphthenic base S. A. E. 30:

Ditto-|.57 zinc oetyl hos hate Ditto+.5 a tin cetyl p osp etc l)itto+.5% manganese cetyl phosphate The compounding agents herein disclosed may have one or more advantages, depending upon the particular compound selected, the proportion utilized, and the environment which the lubrleating oil is to encounter. It should be observed, for example, that even though a compounded oil may be somewhat corrosive to copper-lead or.

urn-silver bearing metals, Babbitt bearings are little if at all aflected by such corrosive action. Hence, compounded oils which may not be particularly desirable for lubrication of copperlead cc cadmium-silver bearings may be highly useful and extremely advantageous in conjunction with the operation of internal combustion oxidized oil samples. This colorimet'er contained two glass cells 50 mm. square by 7 mm. thick set equidistant from a light source consisting of a small electric light. The light from the source impinged on two photoelectric cells after passing through the oil samples contained in "the glass cells. These two photoelectric cells were mounted in two'arms of a Wheatstone bridge sothat the diderences in the two photoelectric currents could be determined. The oil before oxidation was placed in one glass cell and the darkened oil after oxidation was placed in the other. The

di'fierence in light transmission in the two oils was thus measured in a Wheatstone bridge, and the reas given in Table 5 are in terms of the scale on the Wheatstone bridge, dial:

engines having bearings of Babbitt or other corrosive-resistant bearing metals. The present inventlon in its broader aspects is therefore not limited to the use of a particular compound having all or the greatest number of advantages,

' but embraces various of the less advantageous addition agents which will findutlllty in particular applications where all the possible improvement in properties may not be required or where the standard of performance may not be so high.

Present experience indicates that where the properties desired involve the ability to stabilize lubricating oils under severe operating conditions, such as those encountered in the lubrication. of pistons and piston rings of internal combustion engines of the Diesel type, polyvalent metal salts of substituted oxyacids of pentavalent phosphorus containing more than twelve carbon. atoms in the molecule and preferably containing an alkyl or alkaryl substituent should be utilized. It is to be understood that by polyvalent metal salts used in the above connection the alkaline earth metals are included.

a moderately acid refined Western naphthenlc base oil is the preferred oil stock used as a base for the compounded lubricants involved herein. The compounding ingredients appearto function more emclently in such a base oil than in a highly paramnic oil stoclr or a highly refined Western 011. However, it is to be understood that the invention is not limited to any particular base stock since advantages herein disclosed may be obtained at least to some degree with various to inhibit piston ring sticking comprises the principal property desired. Solutions containing more than 2% oi. the compounds in mineral oil may be utilized for the purpose of preparing lubrlcating greases and concentrates capable of dilution with lubricating oils and the like. Such higher concentrations comprise a convenient method of handling the compounds and may be used as addition agents for lubricants in general as well as for other purposes. 1

The metal salts of this invention may be added to hydrocarbon oils containing other compounding ingredients such as pour point (IBDI'GSSOOLS, oilncss agents, extreme pressure addition agents, blooming agents, compounds for enhancing the viscosity index of the hydrocarbon oil, corrosion inhibitors, color stabilizers, etc. The. invention in its broader aspects embraces mineral hydrocarbon oils containing, in addition to metal salts of the substituted acids of phosphorus, thickening agents and/or metal soaps in grease-forming proportions or in amounts insumcient to form greases, as in the case of mineral castor machine oils or other compounded liquid lubricants.

In accordance with the foregoing disclosure, metal salts of metals of the iron family and acids of phosphorus containing an organic substituent may be utilized in lubricating oils in the proportions and for the purposes set forth hereinbefore. Metals of the iron family are known to be: chromium, manganese, iron, cobalt and nickel, and this term as used herein is intended to have this significance.

While the character of the invention has been described in detail and numerous examples of the composition given, this has been done by way of illustration only and with the intention that bait salt of an acid of phosphorus having an organic substituent.

v 3. A-' lubricating composition containing a based on the oil of a salt of a metal of the iron family, said salt. being of an acid of phosphorus containing an organic substituent.

6. A lubricant comprising a hydrocarbon oil and from approximately 0.05% to 2% by weight based on the oil of a cobalt salt of an acid of phosphorus having an organic substituent.

7. A lubricant comprising a hydrocarbon oil and from approximately 0.05% to 2% by weight based on the oil of a nickel salt of an acid of phosphorus having an organic substituent.

8. A lubricant comprising a hydrocarbon oil and from approximately 0.05% to 2% by weight based on the oil of a manganese salt of an acid of phosphorus having an organic substituent. I

9. A liquid lubricating composition comprising a hydrocarbon oil subject to deterioration at elevated temperatures, and a small amount willcient to inhibit said deterioration of a salt of a metal of the iron family, said salt being of an acid of phosphorus having an organic substitu ent.

10. A liquid lubricant composition comprising a hydrocarbon oil subject to deterioration at elevated temperatures, an a small amount suflicient to inhibit said deterioration of a cobalt salt of an acid of phosphorus having an organic substituent.

11. A liquid lubricating composition c0mpris-- ing a hydrocarbon oil subject to deterioration at elevated temperatures, and a small amount surficient to inhibit said deterioration of a nickel salt of an acid of phosphorus having an organic substituent. Y

12. A liquid lubricating composition comprising a hydrocarbon oil subject to deterioration at elevated temperatures, and a small amoimt sumcient to' inhibit said deterioration of arnannanese salt of an acid of phosphorus havingau organic substituent.

BRUCE B. FARRHWGTON. Him 0. CLAYTON. J'bmt T. RUMRFORD. 

